The one from me would be Vieja melanura 'var. synpila' and would be the the more red/blue colored species as it gets mature and most 'like' the Belize fish. The one from my buddy Ryan at global is the melanura likely from Guatemalan stock(at a least at one point was) which is the more orange fish. 2019, all of 2020, and up until the summer of this year I had both populations on hand. The Peten fish (Guatemala) is currently the more well distributed fish available from farms both domestic and internationally in Europe and Asia. It has also been available from myself at TUIC, Max from MaxCichlids, and cota. All 3 of which have sent these to farms and breeders all over the globe.
Below are some photos. 1st and 2nd is the original Belize melanura which was always distributed as 'synspilum - Belize'. The original Belize fish had a more streamlined body. Todays 'Belize' fish seem a bit stockier. The Fish in the photo is from the late 90s and was one of the very first of the Belize 'synspilum'. Myself and Mo Devlin bred that population and they were distributed by TUIC for many, many years. The 3rd photo is todays most common melanura 'var. synspila' and is the current stock that I distribute under that description. That particular population is long time captive bred and the original location is long forgotten. it is a stockier bodied fish and is very well distributed in the hobby. Lastly, is the original Lago Peten melanura, aka the true melanura. That exact pair was imported by TUIC in 2006(ish). They are in breeding color in the 1st photo. I bred that population for nearly 16 years. That is the same fish Jeff Rapps, myself, Max, cota and even Rusty Wessel(privately) have distributed for many years under the Lago Peten description.
While genetically they are all the same fish, the melanura species has a very wide range and each population varies. Often very significantly for one body of water to the very next.
original Belize fish from late 90s:
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Todays common 'synspila':
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The original Lago Peten Guatemala fish:
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